Justification:Cyanea superba was endemic to the island of O'ahu, Hawaii. It was known from the northern Waianae Mountains and the southern Koolau Mountains. Only the Waianae subspecies superba was known to be extant. More than 60 plants in two subpopulations were known in the 1970s. The subspecies (and species) then declined down to only one subpopulation containing about five plants. But those too have now finally gone. The major threats to the species and its habitats were alien plants, feral pigs, slugs and fire.

Cyanea superba was endemic to the island of O'ahu, Hawaii. It was known from the northern Waianae Mountains and the southern Koolau Mountains. The subspecies regina was historically present in the southern Koolau Mountains, but has not been collected since 1932. After its collection in 1870, there were no further documented sightings of Cyanea superba ssp. superba until its rediscovery in the Waianae Mountains in 1971.

The major threats to the species and its habitats included invasive alien plants, predation by feral pigs, and rats and slugs. Other major threats included wildfires generated by activities in the nearby military firing range. The restricted range of the species also made it very vulnerable to small local disturbances, and hence the last few individuals were easily destroyed.